Secondary electric clock.



PATENTED JULY-21, 1903.

T. H. WURMB & R. BAUMANN.

SECONDARY ELECTRIC CLOCK.

APPLICATION FILED MAY 11, 1903.

2 SHEETS-SHEET 1.

N0 MODEL.

nun "Human.Wm......

No. 734,389. PATENTED JULY 21, 1903'. T. H. WURMB & R. BAUMANN.

SECONDARY ELECTRIC. CLOCK.

APPLICATION FILED MAY 11, 1903.

2 SHEETS-SHEET Z- NO MODEL.

111: wcnms warms co. PNOYO-LIYMCL WASHINGTON, u c,

UNITED STATES- Patented July 21, 1903.

PATENT OFFICE.

THEODORE H. IVURMB AND ROBERT BAUMANN, OF ST. LOUIS, MISSOURI.

SECONDARY ELECTRIC CLOCK.

SPECIFICATION forming part of Letters Patent No. 734,389, dated July 21 1903.

Application filed May 11, 1903.

To all whom it may concern:

Be it known that we, THEODORE H.WURMB and ROBERT BAUMANN, citizens of the United States,residing at St. Louis, State of Missouri, have invented certain new and useful Improvements in the Construction of Secondary Electric Clocks, of which the following is a specification containing a full, clear, and exact description, reference being had to the accompanying drawings, forming a part'hereof.

Our invention relates to the construction of secondary electric clocks.

Our objectis, first, to economize in electric power by reducing to a minimum the friction of the mechanism, and, second, our object is to produce an electric-clock motor which may be used with equal facility in a system of small mantel and hall clocks or in larger street and tower clocks or in any kind of ad vertising-clock, as the construction is substantially the same no matter what the size of the clock may be.

Our present invention is designed as an improvement upon the construction shown in our United States Letters Patent numbered 679,546, granted July 31, 1901.

The advantages of secondary electric clocks over mechanical and individual electric selfwinding clocks are apparent and indisputable, as they may be operated as a system throughout large public buildings or residences. In every case the electric movement is always of comparatively small dimensions and may consequently be placed in any desired location and in different positions, so that the designer of the interior finish of offices or rooms in fine residences may have a wide scope for his artistic ability in placing clocks with special designs of dials and hands.

It is well known that the success of secondary electric clocks depends, primarily, upon a positive and reliable contact-maker at the master-clock, and we preferably make use of the adjustable circuit-closer shown and described in our United States Letters Patent numbered 585,301, granted June 29, 1897, although we may of course use any other wellknown circuit-closer for the purpose mentioned.

In operating a number of clocks on a circuit where the power required exceeds the carrying capacity of the circuit-closer we will Serial No. 156,608. (No model.)

of course make use of the well-known practice of connecting with the circuit one or morev common relays, which are to be placed either in the casing of the master-clock or individually with one or more of the secondary clocks.

Our present invention consists, first, of an improved secondary-electric-clock movement arranged to be operated by an electromagnet, which may be of any known form, but preferably is of the construction shown and described in our United States Letters Patent numbered 682,377, granted September 10, 1901.

Our present invention consists, further, of the details of construction hereinafter de= scribed and claimed.

In the drawings, Figure l is a sectional front elevation of our improved secondaryclock movement with the unimportant gears removed. Fig. 2 is a plan view of the same. Fig. 3 is a detail perspective view of our improved connecting-bar made use of in transmitting the reciprocating movement of the armature to the driving-shaft. Fig. 4 is an end elevation of the movement shown in Figs. 1 and 2. Fig. 5 is a perspective view of the driving-shaft and its disconnecting mechanism.

The frame is provided with the usual front and back plates 1 and 2, held together bythe usual screw-bolts 3 and 4c. The yoke 5 of the elect-romagnet 6 is secured to the lower bolts 3 and 4 by means of clamps 7, thereby supporting said electromagnet in a vertical position, as shown.

As previously stated, we do not confine ourselves to the use of any specific form of electromagnet; but said electromagnet should be provided with an oscillating or vibrating armature S, hinged at 9 to one of the projecting cores 10 of the electromagnet. The armature is held in its normal position preferably by means of a suitable spring, although it is clear that any common form of weight may be substituted for the spring or springs. In

the present case we have shown two forms of springs, one of which is that shown at the right hand of Fig. 1, the same being a coiled spring 11, having its lower end connected to a fixed bracket 12, projecting from the electromagnet-yoke 5, and the upper end of said ICO spring being secured to the overhanging end of the said armature 8 by means of a hook 13. In Figs. 1 and 4 the armature is shown in the position to which it is drawn by the power of the magnet when in circuit.

14 indicates a flat spring secured at one end to the projecting core of the electromagnet and extending above the armature toa point above the opposite core and is there provided with an adjusting-bolt 15 and nut 16, carried by the armature.

Of course it will not be necessary to use both forms ofsprings, as shown and described, as it is evident that either form will be sufficient for the purpose, although both forms may be used at the same time, if so desired.

The central or minute-hand shaft 17 carries a large gear-wheel 18, which is driven by the intermediate gear wheel 19, which is mounted upon the stud 20, carried by the frame-plate 2, and motion is communicated to said intermediate gear-wheel by means of the driving-pinion 2i, which is mounted upon the driving-shaft 22. Said driving-shaft 22 is mounted in a rocking frame formed bythe opposite vertical connecting-links 23 and 24 and the rock-shaft 25, upon which said links 23 and 24 are rigidly fixed. The outer ends of the rock-shaft 25 are mounted in the opposite frame-plates l and 2.

Movement is imparted to the rocking frame by means of a horizontal arm or lever26, extending laterally from the lower end of the link 24 to a point beyond the frame-plates l and 2, and its outer end is provided with a suitable aperture 27 to accommodate achain, rope, or wire for the purpose of adding a weight (not shown) in order to keep the pinion 21 in mesh with the intermediate wheel 19. The arm or lever 26 may also he used for the purpose of rocking the frame which carries said pinion in order to disengage the same from the said intermediate wheel 19 whenever it is desired to disengage the clockmovement from the motor mechanism, as requiredin setting the hands and for other purposes.

A pin-wheel 28 is formed of a disk having a series of short pins 29, projecting from one of its sides, and is fixed upon the drivingshaft 22.

Projecting laterally from the armature 8 is a pin 30, forming a journal for the bearing 31 at the upper end of the connecting-bar 32. Said connecting-bar is provided in its lower portion with a guide-slot 33, through which passes the driving shaft 22, and thereby guides the lower end of the said connectingbar during its reciprocations.

A push-pawl 34 is pivotally connected at its upper end to the connecting-bar 32 by means of a pivot 35, and said pawl is provided with a lateral projection 36, which consecutively engages the pins 29 of the said pinwheel 28 whenever the armature 3 is attracted by the electromagnet. The push-pawl 34 is provided at its lower end with a weight 37,

which also acts as a stop to limit the inward movement of the push-pawl.

Fixed upon the connecting-bar 32 at a point directly above the driving-shaft is a lockinglug 38, the lower end of which is sharpened, and fixed upon the lower portion of the said connecting-bar directly beneath said drivingshaft is another locking-lug 39, the upper end of which is sharpened. These locking-lugs are adapted to alternately engage between two adjacent pins 29 in order to rigidly lock the pin-wheel 28 at the completion of each stroke made by the armature and its connecting-bar. For instance, when the connectingbar is up the lower locking-lug 39 engages between two of the pins 29, and when the connecting-bar is at the limit of its downwardstroke the upper locking-lug 38 will be projected between two teeth of the pin-wheel.

Retrograde movement of the pin-wheel 28 is prevented at all times by the spring-pawl 40, the upper end of which engages beneath the pins 29 and the lower end of which is fixed to some part of the rocking frame, preferably the enlarged portion 41 of the rockshaft 25, as shown clearly in Fig. 5. Said spring-pawl is not essential and may be dispensed with in some cases, as it merely acts as a safeguard in case of extraneous interferencewiththeclock-hands. (Notshown) The device herein shown is a minute movement, the gear-wheel 18 preferably having sixty teeth and the pin wheel 28 twelve pins 29.

The operation is as follows: Sixty consecutive contacts at the master-clock will produce that many attractions of the armature S, which through the connecting-bar 32 and the intermediate gearing will turn the gearwheel 18 one complete revolution. For half or quarter minute movements the gearing will necessarily be modified in the usual mannor to suit the service desired. Upon closing the circuit through the electromagnet the armature 8 will be attracted and descendto the position in which it is shown in Figs. 1 and 4, and this will carry downwardly the connecting-bar 32 and its push-pawl 34, and its projection 36 will engage the pin 29 directly beneath said projection, and the said pinwheel 28 will be thereby moved one step, and

the motion will be communicated to the hands of the clock through the gearing. As the said connecting-bar 32 moves downwardly the lower locking-lug 39 will be disengaged from the pins of the pin-wheel, and the upper locking-lug 38 will be projected between two of said pins, and thereby lock the movement until the same is released by the retraction of the armature by means of its spring or retractile device, and the operation is repeated as long as the movement is in running order. When the push-pawl 34 is descending, the pin 29, which is in contact with the lower locking-lug 30, will follow the incline of the said lug, and before the point of said lug passes below the said pin the upper locking-lug 38 will enter between two pins. at a point diametrically opposite said lower lock ing-lug, thereby not only looking the pinwheel while the armature is closed, but making it practically impossible without outside interference for the wheel to turn more than one step at a time. The spring-pawl 40 consecutively engages the pins and prevents the pin-wheel from being turned backward by the push-pawl 34 while the latter is returning to its normal position. The push-pawl 34, acting upon the pins of the pin-wheel 28, provides ample leverage for the movement of said pin-wheel for the reason that the distance of the pins from the center of the driving-shaft 22 is two and one-half or three times that of the pitch-line of the pinion 21 from its center, and as there is 'no friction or resistance caused by complicated mechanism all the power that is required for operation is to overcome the inertia of the few small gears and that of the hands of the clock. It will thus be seen that our improved mechanism is very simple in construction and operation.

The hands of the clock can be reset by elevating the arm 26, which will thereby move the rocking frame and the driving-shaft 22, together with its pinion 21, until said pinion is thrown out of mesh with the gear-wheel 19, thereby allowing the hands to be turned freely in either direction. Upon releasing the arm the rocking frame will return to its normal position by its own weight, and the pinion 21 will again mesh with the gear-wheel 19.

What we claim is 1. In asecondary-electric-clock movement, an electromagnet, an armature therefor, means for retracting said armature, a drivingshaft, a suitable train of gearing connected to said driving-shaft, a reciprocating connecting-bar arranged to move with said armature, means for guidin g said connectingbar, a pawl carried by said connecting-bar, a pin-wheel operated by said pawl and connected to said driving-shaft, and a suitable stop for locking said pin-wheel against movement except when the same is actuated by the said pawl, substantially as specified.

2. In asecondary-electric-clock movement, an electromagnet, an armature therefor,

an electromagnet, an armature therefor, means for retracting said armature, a drivingshaft, a suitable train of gearing connected to said driving-shaft, a reciprocating connectin g-bar arranged to move with said armature, means forguiding said connecting-bar, a pawl carried by said connecting-bar, a pin-wheel operated by said pawl and connected to said driving-shaft, and two stops for locking said pin-wheelagainst movement in either direction except when actuated by the said pawl; said stops having inclined faces and adapted to engage alternately between two pins of the said pin-wheel, substantially as specified.

4. In a secondary-electric-clock movement, an electromagnet, an armature therefor, means for retracting said armature, a drivingshaft, a suitable train of gearing connected to said driving-shaft, a reciprocating connecting-bar arranged to move with said armature, means for guiding said connecting-bar, apawl carried by said connecting-bar,a pin-wheel operated by said pawl and connected to said driving-shaft, a suitable stop for locking said pin-wheel against movement except when the same is actuated by the said pawl, and a rocking frame carrying said driving-shaft, pinion and pin-wheel, whereby said pinion may be thrown out of mesh with its connecting gearwheel, substantially as specified.

In testimony whereof we have signed our names to this specification in presence of two subscribing witnesses.

THEODORE H. WURMB. ROBERT BAUMANN. Witnesses:

ALFRED A. EIoKs, M. G. IRION. 

